Biomedical subjects

Jian-Min Wan

Publications and source records attributed to Jian-Min Wan.

31 records · Page 2Linked to original sources

PubMed2004

[Stable expression of QTL for grain shape of milled rice (Oryza sativa L. ) using a CSSLs population].

A set of chromosome segment substitution lines (CSSLs), derived from Asominori/IR24 with Asominori as the recurrent parent,was planted and phenotyped for grain length (GL), grain width (GW) and length-width ratio (LWR) of milled rice in two successive years and four sites. QTL for GL,GW and LWR were characterized and stability of their expression was investigated. The phenotypic values for each trait showed a continuous distribution and some transgressive lines were also observed in the CSSLs population. Additionally, a total of 13 QTL for GL, GW and LWR were identified,and six of them were consistently detected in the eight different environments. Phenotypic values were different significantly (P < 0. 001) between the CSSLs harboring any of the six QTL alleles and the genetic background parent, Asominori. Significant phenotypic correlations (r > or = 0.75, r0.05 = 0.67) were detected among different environments for these CSSLs carrying the same target QTL. Also, the results indicated that the six QTL, namely, qGL-3 for GL, qGW-5a and qGW-5b for GW, qLWR-3, qLWR-5a and qLWR-5b for LWR, were stably expressed in different environments. Since QTL qGL-3 and qLWR-3 were mapped in the R19-C1677 interval, qGW-5a and qLWR-5a in the vicinity of RFLP marker C263, qGW-5b and qLWR-5b near R569,the four RFLP markers, R19, C1677, C263 and R569,would be useful for further marker-assisted selection (MAS) in rice quality improvement.

Chromosomes, Plant↗

PubMed2003

Induced expression of the gene for NADP-malic enzyme in leaves of Aloe vera L. under salt stress.

A cDNA fragment for NADP-malic enzyme, catalyzing the reversible oxidative decarboxylation of L-malate to produce CO(2), pyruvate and NADPH, was isolated from the leaves of a 2-month-old Aloe vera L., The level of expression of NADP-ME mRNA and accumulation of NADP-ME (AvME) protein under salt stress conditions were compared between a tolerant aloe, Aloe vera L. and a sensitive aloe, Aloe saponarea Haw. The results suggested that both the expression of the gene and the accumulation of the protein were induced in the two kinds of aloe, and the strength was related to the degree of salt tolerance. Northern blot analysis revealed that the gene for NADP-malic enzyme in Aloe vera L.( AvME) was induced by high salt, dehydration, and exogenous abscisic acid (ABA), but not by cold treatment. To further confirm whether the synthesis of AvME protein was induced with hours of treatment, Western blot analysis of the samples was conducted. The results indicated that the induction of AvME protein expression was obvious after 48 h at high salt and the level was increased with the hours of treatment.

Abscisic Acid↗

PubMed2003

QTL and epistatic interaction underlying leaf chlorophyll and H2O2 content variation in rice (Oryza sativa L.).

It is meaningful to study the genetics of the traits associated with photosynthesis such as leaf chlorophyll and H2O2 contents for high yield breeding in rice. A mapping population of 98 BC1F9 lines (backcross Inbred Lines, BIL), derived from a backcross of Nipponbare (japonica)/Kasalath(indica)//Nipponbare by the single-seed-descent methods, was employed to map quantitative trait loci (QTL) underlying such rice traits as leaf chlorophyll and H2O2 contents. Five and two QTLs were detected for leaf Chlorophyll and H2O2 content variation, respectively. Among the QTLs detected, q-Chl1 on chromosome 1 accounted for 22% variation for leaf chlorophyll content variation. The alleles from Nipponbare increased stature at the locus; On the other hand, q-H2O2(1) which associated with H2O2 content was also located on the same region as q-Chl1. The alleles from Nipponbare decreased stature at this locus. The 2 traits have the 2 QTL sharing the same chromosome locations, which was located between C86 and C813 on chromosome 1. Epistasis analysis showed QTL with interaction distributed on chromosome 2, 6, 11 and 12. However, no QTL interacted with q-Chl1 or q-H2O2(1) was detected. It can be deduced that alleles from Nipponbare at the region between C86 and C813 on chromosome 1 increases leaf chlorophyll content and decreases H2O2 content at the mean time with significant additive effect but little epistasis.

Chlorophyll↗

PubMed2003

Mapping quantitative trait loci underlying appearance quality of rice grains (Oryza sativa L.).

Ninety-eight backcross inbred lines (BILs) derived from a subspecific cross of Nipponbare (japonica)/Kasalath (indica)//Nipponbare and its genetic linkage map were used to identify quantitative trait locus (QTL) controlling rice appearance quality traits such as grain length (GL), grain width (GW), length-width ratio (LWR), percentage of grains with chalkiness (PGWC), square of chalky endosperm (SCE), degree of endosperm chalkiness (DEC) and grain endosperm transparency (GET) by composite interval mapping over two years. A total of 33 QTLs were identified to be significant in at least one year for seven traits and the number of QTL for each trait ranged from four to seven, showing that appearance quality of rice grains were controlled by multigenes. The phenotypic variation explained by individual QTLs ranged from 6.2% to 15.2% for GL, 8.3% to 32.5% for GW, 6.8% to 19.8% for LWR, 6.4% to 28.5% for PGWC, 6.1% to 16.9% for SCE, 9.3% to 17.2% for DEC, and 5.6% to 25.2% for GET. The distribution of QTL were characterized by clustering with the intervals of C1488-C563 on chromosome 3, R830-R3166 and R1436-R2289 on chromosome 5, R2147-R2171 on chromosome 6 each harboring over 3 QTLs. The QTL-by-environment interactions were observed by comparing QTL mapping of the same population grown in 2 consecutive years, but were trait dependent. The QTL for GL and LWR were rather stable across years while that for PGWC, SCE and DEC were very sensitive to environments.

Chromosome Mapping↗

PubMed2003

[Detection and analysis of QTL for seed dormancy in rice (Oryza sativa L.) using RIL and CSSL population].

A recombinant inbred line (RIL) population and two chromosome segment substitution line (CSSL) population derived from the cross of Asominori (japonica) and IR24 (indica) were used to detect QTL controlling seed dormancy. CSSL1 were a series of IR24 chromosome segment substitution lines in Asominori background, and CSSL2 were a series of introgression lines of Asominori in the background of IR24. Three QTL were detected on chromosome 3, 6 and 9 in RIL population, and individual QTL accounted for between 12.3% and 13%. Three QTL were detected on chromosome 1, 3 and 7 in CSSL1, and individual QTL accounted for between 11.5% and 18.9%. Three QTL were detected on chromosome 1, 2 and 7 in CSSL2, and individual QTL accounted for between 11% and 16%. The QTLs on chromosome 1 and 7 were detected in CSSL1 and CSSL2 populations simultaneously, QTL came from Asomonori, the moderate dormant cultivar, increased seed dormancy, and QTL from IR24, the weakly dormant cultivar, decreased seed dormancy. It can be deduced that there exist genes controlling seed dormancy at this region.

Chromosome Mapping↗

PubMed2003

[Analysis of photoperiod-sensitivity genes in Minghui63, an restorer line of indica rice(Oryza sativa L.)].

Hybrid rice is very important in agriculture production in China. Its selecting property makes it significant to study the genetic performance of F1's date to heading (DH). Minghui63, an indica rice restorer line, has been widdly applied to hybrid rice seed production in China, but the photoperiod-sensitivity gene of heading date in this restorer line is still unknown. This definitely limited the further use of this restorer line in breeding practice and re-production of hybrid seeds. To solve this problem, using heading time nearly isogenic lines EGO-EG7, ER-LR and two heading date QTL-isogenic lines, NIL (Hd1) and NIL (Hd4), with the genes of Nipponbare but Hd1 (Se-1) and Hd4 (E1) genes from Kasalath, respectively, we performed a genetic analysis of Minghui63 with special reference to photoperiod-sensitivity loci, using natural long days in Nanjing(32 degrees N) and natural short days in Linshui county, Hainan province (18 degrees 29'N), where the average day-length is about 14 h and 11.6 h during the course of rice growing, respectively. The F1 and F2 generations from the crosses "heading time nearly isogenic lines x Minghui63" were subjected to genetic analyses. Experimental results showed that Minghui63 carries photoperiod-sensitivity allele gene E1 and E3 in E1 and E3 loci, respectly, and a photoperiod insensitivity allele Se-1e in Se-1 locus, and it also carries a recessive inhibitor for photoperiod-sensitivity gene E1. Meanwhile, the photoperiod-sensitive genes, E1 and the photoperiod-insensitive genes, Se-1e, in Minghui63 were also identified by crossing with the nearly isogenic lines for heading time QTLs, NIL (Hd1) and NIL(Hd4). The results indicated that Minghui63's genotype of heading date was: E1E1e2e2E3E3Se-1eSe-1e. The result from this research indicated that Minghui63 carries a major dominant photoperiod-sensitive gene E1 in E1 locus, and our previous researches indicated that Zhenshan97A carried a major dominant photoperiod-sensitive gene Se-1n in Se-1 locus and a recessive inhibitor gene i-Se-1. The DH of the hybrid rice "Shanyou63" is 94.7 in Nanjing, lying between Zhenshan97A's and Minghui63's, but more nearer to late maturity parent Minghui63. It has been not expressed that E1 gene usually prolongs days to heading by about 20 days when coexisting with Se-1u or Se-1n. This is possibly made by that inhibitor genes exist in respective parents, which make DH transgression of "Shanyou63" not appear. This phenomenon indicated that the heading date of indica hybrid rice is resulted from the interaction among the photoperiod-sensitive genes and their inhibitor genes in the sterile and the restorer lines.

Gene Expression Regulation, Plant↗

PubMed2003

[Screening and genetic analysis of rice glutelin mutant].

The contribution of rice as a protein source is important. Rice seed protein can be divided into four forms, glutelin (57 kDa, 37-39 kDa, 22-23 kDa), prolamine (13 kDa), albumin (16 kDa) and globulin (10 kDa, 26 kDa) on its solubility. Glutelin is the major storage protein of rice and accounted for 80% of total protein found in the rice grain, the mature glutelin comprises an acidic (37-39 kDa) and an basic subunit (22-23 kDa) coming from a common precursor (57 kDa) by post-transcriptional hydrolytic cleavage. Prolamine is the second important. Rice seed proteins localize in two types of protein bodies, PB-I, PB-II. PB-I containing prolamine is indigestible, whereas PB-II being rich in glutelin is digestible. The nutritional value of rice could thus be raised by improving its digestible protein glutelin content. On the other hand, the character of low digestible protein is also an important target of rice breeding. Low protein rice is required for the diet of patients with kidney disease. Three glutelin mutants, W3660, W204, W379, were found by screening 168 rice varieties through SDS-PAGE analysis of the seeds total proteins. The amounts of 37-39 kDa and 22-23 kDa glutelin subunits were much lower and that of 13 kDa prolamine polypeptide was higher in W3660 seeds than in ordinary rice; The amounts of 37-39 kDa and 22-23 kDa glutelin subunits in W204 or W379 seeds were between those in W3660 and ordinary rice. Especially, in W379 seed, there was a large quantity of 57 kDa polypeptide. For characterizing the genetics of the glutelin mutant, the cross population between W3660 and Otorokimochi was constructed. SDS-PAGE analysis of the progeny seed total proteins showed, low glutelin content was always accompanied by high prolamine content; all F1 seeds had low glutelin and high prolamine content; the segregation of low glutelin and normal type in F2 seeds was 3:1; the genotypes of F2 plants were deduced by the analysis of F3 seeds, and among F2 plants the ratio of homozygotes of low glutelin, heterozygotes of low glutelin and homozygotes of normal type was about 1:2:1. These results proved that the trait of low glutelin and high prolamine was controlled by a single dominant gene and could be inherited by its progeny.

Glutens↗

PubMed2003

Hepatitis gene chip in detecting HBV DNA, HCV RNA in serum and liver tissue samples of hepatitis patients.

OBJECTIVE: To study the preparation of diagnostic gene chip for detecting hepatitis B virus (HBV) and hepatitis C virus (HCV) and its accuracy in detecting HBV DNA and HCV RNA in serum and liver tissues. METHODS: The probes, which depend on the conservative gene fragment of hepatitis virus, was designed, synthesized and spotted on the modified glass. The probes and some other control probes were assembled on the diagnostic microarray of hepatitis virus. The gene of hepatitis virus, purified from blood or tissue, was labeled with fluorescence and hybridized to the microarray. The hybridized microarry was scanned with microarray scanner and the diagnostic result was analyzed from the scanning data. Fourty patients with hepatitis B virus and 40 healthy people or 40 patients with hepatitis C virus were subjected to detection of HBV DNA and HCV RNA with the hepatitis virus gene chip by the double-blind method. Paraffin liver specimens obtained from 99 cases of posthepatitic cirrhosis were used to detect HBV DNA. The liver tissues and serum from 15 cases of chronic hepatitis B were used to detect HBV DNA. Simultaneously, HBsAg and HBcAg were detected in the serum by fluorescence microparticle quantitation, HBV DNA and HCV RNA in the serum by PCR, and HBcAg in liver tissues by immunocytochemistry or HBV DNA by in situ molecular hybridization. RESULTS: Chip detection of serum specimens showed that 30 patients were HBV DNA positive and 10 HBV DNA negative in the 40 patients with HBV positive, 25 patients were HCV RNA positive and 15 patients were HCV RNA negative in the 40 patients with HCV positive, and all were HBV and HCV negative in the 40 healthy people. In 15 patients with HBV marker positive who were subjected to liver biopsy, 15 patients were detected HBV DNA positive in serum by gene chip, 15 patients HBcAg positive in liver tissues by immunocytochemistry, 14 patients HBV DNA positive in liver tissues by in situ molecular hybridization, and 14 patients HBV DNA positive in liver tissues by gene chip. Paraffin liver tissues specimens from the 99 patients with posthepatitis B cirrhosis showed that 67 patients were detected HBcAg positive by immunocytochemistry, 53 patients HBV DNA positive by in situ molecular hybridization, and 46 patients HBV DNA positive by gene chip. In the 46 patients, 40 patients were detected HBV DNA and HBcAg positive by in situ molecular hybridization and immunocytochemistry, 6 patients only HBcAg positive, and 33 patients HBcAg negative. CONCLUSIONS: The designed diagnostic gene chip can be used to simultaneously detect serum HBV DNA and HCV RNA, but the positive rate of HCV RNA diagnosed by this chip is lower. The gene chip can detect HBV DNA in serum and in liver tissue.

DNA, Viral↗

PubMed2003

Mapping QTL for traits associated with resistance to ferrous iron toxicity in rice (Oryza sativa L.), using japonica chromosome segment substitution lines.

A mapping population of 66 japonica chromosome segment substitution lines (CSSLs) in indica genetic background, derived from a cross between a japonica variety Asominori and an indica variety IR24 by the single-seed descent, backcrossing and marker-assisted selection, was used to detect quantitative trait loci (QTLs) for leaf bronzing index (LBI), stem dry weight (SDW), plant height (PH), root length (RL) and root dry weight (RDW) under Fe2+ stress condition in rice. Two parents and 66 japonica CSSLs were phenotyped for the traits by growing them in Fe2+ toxicity nutrient solution. A total of fourteen QTLs were detected on chromosome 3, 6, 7, 9, 11 and 12, respectively, with LOD of QTLs ranging from 2.72 to 6.63. Three QTLs controlling LBI were located at the region of C515-XNpb279, R2638-C1263 and G1465-C950 on chromosome 3, 9 and 11, their contributions to whole variation were 16.45%, 11.16% and 28.02%, respectively. Comparing with the other mapping results, the QTL for LBI located at the region of C515-XNpb279 on chromosome 3 was identical with the QTL for chlorophyll content on a rice function map. The results indicated that ferrous iron toxicity of rice is characterized by bronzing spots on the lower leaves, which spread over the whole leaves, causing the lower leaves to turn dark gray and to product chlorophyll catabolites or derivatives which reduce cytotoxicity of some heavy metals, such as ferrous iron. Furthermore, the QTL for LBI, SDW and RDW located at the region of G1465-C950 on chromosome 11 is a major QTL. Whether the QTL for SDW, PH, RL and RDW at the region of XNpb386-XNpb342 on chromosome 6 is associated with resistance to ferrous iron toxicity need further studies. Our goal is to identify breeding materials for resistance to Fe2+ toxicity through marker-assisted selection based on the detected markers.

Chromosome Mapping↗

PubMed2003

Chromosomal location and expression of green fluorescent protein (gfp) gene in microspore derived transgenic barley (Hordeum vulgare L.).

Four doubled haploid barley lines (A, C, D, E) derived from gfp (green fluorescent protein) transformation and selection following particle bombardment of microspores were studied for gene expression pattern and the location of genome inserts. The integration sites were detected by fluorescence in situ hybridization (FISH) using the gfp plasmid DNA as a probe. Plants from events A, C, D and E all have a single insert site on chromosome 7L(5HL) at different locations while line E has a second insert site on chromosome 5S(7HS). All original transgenic plants were hemizygous for the transgenes and segregated in the T1 and T2 generations. Although line D had no GFP expression, FISH and PCR could detect gfp gene on its chromosome in transformed plants. Expression levels of GFP varied with lines and tissues examined. Plants from line C showed good expression in pollen and an intermediate level in root tips. Plants from A have intermediate expression of GFP in the pollen and light expression in the root tips. Line E showed strong expression in the root-tips and an intermediate level of GFP in the pollen. Lines A and C segregated as a single Mendelian locus while E segregated in a duplicate loci ratio (15:1) on seedling root tips but had low expression frequency in the pollen. PCR results were consistent with GFP expression on root tips in the three segregating lines. The expression of GFP for lines D and E was abnormal and may be related to the physical location of the transgene or the gene construct used.

Chromosome Mapping↗

PubMed2003

[A novel method of extracting total RNA from rice embryo samples].

A novel and simple CTAB-LiCl-based extraction method for high-quality and total RNA of rice embryo samples is developed. This method can efficiently eliminate the interference of polysaccharide and lipids rich in rice (Oryza sativa L.) embryo obtained under room temperature without using liquid nitrogen. The results of ultraviolet spectrophotometer and agarose gel electrophoresis analysis show that the obtained RNA has no obvious degradation and a good purity sufficient for further RT-PCR and RNA gel blotting. Therefore, it is also especially useful for the RNA extraction of plant material plenty of polysaccharide and lipids.

English Abstract↗

PubMed2002

[Detection and analysis of QTL for resistance to the brown planthopper, Nilaparvata lugens (Stål), in rice (Oryza sativa L.), using backcross inbred lines].

A mapping population of 98 BC1F9 lines (backcross inbred lines: BILs), derived from a backcross of Nipponbare (japonica)/Kasalath (indica)//Nipponbare by the single-seed descent methods, was used to detect quantitative trait loci (QTL) for resistance to brown planthopper (BPH), Nilaparvata lugens (Stål). Seedbox Screening Technique (SST) was applied to evaluate the reactions of two parents and 98 BILs to BPH at the seedling stage, and the entries were graded on ratio of dead seedlings. A total of three QTL controlling BPH resistance were detected on chromosomes 2, 10 and 12, respectively. Individual QTL accounted for between 10.4% and 16.6% of the phenotypic variance, and the resistance of all the three QTL came from Kasalath, the moderate resistance parent. These QTL should be useful in breeding of varieties resistant to BPH in marker-assisted selection (MAS) program.

Chromosome Mapping↗

PubMed2002

[Identification of quantitative trait loci controlling F2 sterility and heading date in rice].

Ninety-six F2 lines derived from a cross between a japonica cultivar Taichung 65 and an indica cultivar Bhadua were developed. At the first step, an RFLP linkage map based on the F2 lines was constructed. The RFLP map contained 94 RFLP makers. F2 sterility and heading date are important agronomic traits of rice; meanwhile heading date is related to many characters of agronomic importance including sterility. Quantitative trait locus (QTL) analysis was carried out to identify genes controlling F2 sterility and heading date. Both single factor analysis and interval analysis were applied for QTL analysis. Two QTLs for F2 spikelet sterility were newly detected on Chromosome 1 and 8. Five QTLs for heading date were detected on Chromosome 1, 4, 6, 8 and 10. Two of them on chromosome 1 and 10 were newly detected. Near-isogenic lines are now under construction for further QTL analysis and gene mapping of these QTLs newly identified in this paper.

Chromosome Mapping↗